Corrosion Inhibition and Adsorption Properties of Ethanolic Extract of Calotropis for Corrosion of Aluminium in Acidic Media

Table 4

Mass loss data for aluminium in 1.0 N sulfuric acid with ethanolic extract of leaves, latex, and fruit of Calotropis gigantea.

Inhibitor concentration	Mass loss (gm)	Inhibition efficiency (%)	Corrosion rate (mmpy)	Surface coverage (θ)
Uninhibited	2460		44.3
Leaves
0.12	1262	48.69	22.7	0.4869
0.24	957	61.09	17.2	0.6109
0.36	734	70.16	13.2	0.7016
0.48	641	73.94	11.5	0.7394
0.60	523	78.73	9.42	0.7873
Latex
0.12	1244	49.43	22.4	0.4943
0.24	950	61.38	17.1	0.6138
0.36	763	68.98	13.7	0.6898
0.48	619	74.83	11.1	0.7483
0.60	521	78.82	9.39	0.7882
Fruit
0.12	1164	52.68	20.9	0.5268
0.24	934	62.03	16.8	0.6203
0.36	727	70.44	13.1	0.7044
0.48	651	73.53	11.7	0.7353
0.60	543	77.92	9.78	0.7792